The present disclosure is generally related to technologies used for suppressing sharp noise from audio signals, and more specifically for suppressing sharp noise from a preprocessed audio signal based on information determined from reference noise associated with the preprocessed audio signal.
A signal receiver can receive a target signal that arrives at the signal receiver along a predetermined direction and an ambient noise signal (or simply ambient noise) that arrives at the signal receiver along one or more directions different from the predetermined direction. For example, an audio receiver of a mobile device receives (i) a speech signal (or simply speech) that arrives at the audio receiver along a “speech direction”, from where a user of the mobile device is expected to speak, and (ii) ambient noise along other directions, different from the speech direction.
As a level of typical ambient noise is lower than a level of the target signal, conventional technologies can be used for suppressing the ambient noise without distorting the target signal, thus forming a “beam” of the target signal that appears to have been received at the signal receiver along the predetermined direction. However, if the ambient noise includes portions of sharp noise, characterized by short durations during which a level of the sharp noise exceeds the level of the target signal, then the portions of the sharp noise will be included in the formed beam of the target signal, when such conventional technologies are used for suppressing the ambient noise. In the foregoing example of the audio receiver, as a level of the typical ambient noise is lower than a level of the speech, conventional technologies can be used for suppressing the ambient noise without distorting the speech, thus forming a “speech beam” that appears to have been received at the audio receiver along the speech direction. However, if the ambient noise includes portions of sharp noise, e.g., sharp noise caused by a plate hitting the floor or by keyboard clicks, such that a level of the sharp noise exceeds the level of the speech, then the portions of the sharp noise will be included in the formed speech beam, when conventional technologies are used for suppressing the ambient noise.